Application package for powder coatings
Methods and systems for coating metal substrates are provided. The methods and systems include a powder coating composition comprising a polymeric binder and an application package. The application package includes at least one antistatic component and at least one post-blended component. Use of the application package reduces back ionization and faraday cage effects during electrostatic application. The described methods provide coatings with optimal surface smoothness and edge coverage.
1. A method for coating a substrate at one or more corners, comprising:
providing a metal substrate;
applying a first powder coating composition;
applying a second powder coating composition over the previously applied non-gelled first coating composition, the second composition comprising:
at least one polymeric binder resin; and
an application package including
an antistatic component; and
a highly dispersed fumed metal oxide component with agglomeration particle size of 5 to 50 nm.
2. The method of claim 1 , wherein the application package comprises
0.1 to 2 wt % of a quaternary ammonium salt as an extrudable antistatic component; and
0.01 to 1 wt % of a fumed metal oxide as a post-blended highly dispersed component.
3. The method of claim 1 , wherein a cured film formed by the powder coating composition on a corner of the substrate has 20-degree gloss of at least 60.
4. The method of claim 1 , wherein a cured film formed by the powder coating composition on a corner of the substrate has 60-degree gloss of at least 60.